Iridium spark plugs (2008)

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I cannot imagine how one cd keep the recommended sharp edges by using a media blaster.
What's wrong with a brass wire brush?
The grit doesn’t visibly abrade the steel.

A brass wire brush can leave a conductive residue on the ceramic insulator.
 

SteveA

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..........
What's wrong with a brass wire brush?
Wire brushing tends to damage the insulator and cause tracking of the spark....not good for expensive plugs....

Iridiums are not designed to be cleaned, their design is to accommodate staying in a motor pretty much for the life of the motor. Of course that only works with a refined fuel injection system that keeps them clear of excess fuel!

I use iridiums in race motors where you are going to be replacing plugs long before they are life expired.
 

xbacksideslider

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Sheesh . . . . IIRC, my iridiums haven't seen daylight in the best part of ten years.

Tri-Spark, PWK flatslides from Jim Schmidt, and Denso iridiums. No problems . . . and I set the gaps wide too.
 

SteveA

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Sheesh . . . . IIRC, my iridiums haven't seen daylight in the best part of ten years.

Tri-Spark, PWK flatslides from Jim Schmidt, and Denso iridiums. No problems . . . and I set the gaps wide too.

Says as much for the carburation as the plugs/ignition! :D

Yes I prefer Denso, not least because there are less fakes out there than with NGK! I have never set a gap on then, just install straight from box!
 

xbacksideslider

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Yes, :D thanks. Agreed, there is no necessity to widen the gaps, the factory sets them to a common denominator and they function perfectly but I pay extra for them in order to get what they do best - bridge big spark gaps.

I think I can use the word "always" here; all things equal, a long fat spark is always better.

Yes, that wide gap speaks to all three - mixture, ignition and plugs. Electronic ignition ensures the power to bridge a wide gap; sharp pointed plugs enable that wide gap to be even wider, and that longer spark attenuates low speed inadequacies of fuel atomization. In other words, they help transitional mid-range; when the mixture's confused, they help.

I learned a related thing when using accelerator pump carbs on Ducati singles, fine point plugs help there too for, I imagine, the same reason - any momentary richness that the accelerator pump may cause can be cured (or masked ;)) with a stronger spark. Those bikes needed help coming off corners, pumpers and platinum :D .
 

baz

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Yes, :D thanks. Agreed, there is no necessity to widen the gaps, the factory sets them to a common denominator and they function perfectly but I pay extra for them in order to get what they do best - bridge big spark gaps.

I think I can use the word "always" here; all things equal, a long fat spark is always better.

Yes, that wide gap speaks to all three - mixture, ignition and plugs. Electronic ignition ensures the power to bridge a wide gap; sharp pointed plugs enable that wide gap to be even wider, and that longer spark attenuates low speed inadequacies of fuel atomization. In other words, they help transitional mid-range; when the mixture's confused, they help.

I learned a related thing when using accelerator pump carbs on Ducati singles, fine point plugs help there too for, I imagine, the same reason - any momentary richness that the accelerator pump may cause can be cured (or masked ;)) with a stronger spark. Those bikes needed help coming off corners, pumpers and platinum :D .
How wide do you go with your plug gaps?
 

xbacksideslider

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I don't recollect with the Norton. With all my vehicles, I widen them until I get a miss under load, then, having gone too far, I go back, narrower. My typical experience though is 30 or 35 thou.
 

baz

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I don't recollect with the Norton. With all my vehicles, I widen them until I get a miss under load, then, having gone too far, I go back, narrower. My typical experience though is 30 or 35 thou.
Ok cheers
 
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I also bought Iridium for my 805 MKIIA and will not again waste money for Iridium. Personally found no benefit.
 
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On my R100GS it made a slight difference in low RPM tractability. I have not tried them in my Norton for the above reason.
Would be interested in hearing if anyone here still media blasts clean their sooty plugs with the specialty plug blaster tool.
I put spark plugs in my blast cabinet all the time with fine results. Just a quick blast with medium fine glass beads cleans them with no visible erosion of the electrodes.

Aircraft spark plugs are cleaned like that all the time due to lead build up. Many pilots were taught not to lean the mixture below 5000' and aircraft fuel systems are generally set up for rich mixture for cooling in takeoff and climb. Avgas, even the low lead variety, has lots of lead still.

Anyway, a wire brush cannot clean the insulator very well and a quick blast of glass beads will. Wash out with brake cleaner followed by a blast of air and there's no grit left to hurt anything.
 

xbacksideslider

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Yes, nothing wrong with blasting plugs if you have sharp eyes (or an old Champion spark plug lighted loup) to look for any glass bead that might be wedged between the insulator and the shell. Then use a sewing needle to dislodge.
 
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